Calculating device



Oct. 24, 1961 R. E. sTEvENsoN CALCULATING DEVICE Filed Oct. 30, 1958nited `State My invention relates primarily to means of a simple natureadapted to be manipulated directly by a user and designed especially forthe easy computation of elapsed time. Such a device is especially usefulin computing elapsed time for making up time studies, payrolls and thelike. While the device has other applications, it is re ferred toprimaly and is disclosed herein especially as an elapsed timecalculating device.

It is an object of the invention to provide a calculating device readilymanufactured from simple materials and easily fabricated, repaired andused.

Another object of the invention is to provide a calculating device whichcan easily be manipulated by the user, in some instances using but thethumb and one finger of one hand. u

A still further object of the invention is to provide a calculatingdevice-so arranged as to be readily used as a desk implement in anoffice.

Another object of the invention is to provide a calculating device fordirect manual operation and so that auxiliary equipment is not necessaryfor its operation.

A still further object of the invention is to provide a calculatingdevice generally an` improvement over calculating devices heretoforeknown.

While the invention can be incorporated in a number of different waysparticularly dependent upon its immediate iield of use, it hassuccessfully been incorporated as described in the accompanyingdescription and as illustrated in the accompanying drawing, in which:

FIGURE l is a partially exploded view showing various parts of thecalculating device in perspective.

FIGURE 2 is a plan of a calculating device constructed in accordancewith the invention, the users hand being shown in the act of performinga calculation.

FIGURE 3 is a cross-section to an enlarged scale, the plane of sectionbeing indicated by the line 3 3 of FIG- URE 2.

In the present instance the calculating device is especially arrangedfor calculating elapsed time, the time being considered not only inhours but also in tens of minutes and in minutes; For that use themechanism includes primarily a base 6 generally rectangular in planhaving a top edge 7, a bottom edge 8 parallel thereto and two parallelside `edges 9 and' 11 to define a rectangle. Conveniently, :the base isfabricated of metal, plastic or fairly heavy fibel-board, beingpreferably made up of a plurality of superposed sheets of iiberboardadhesively secured together in appropriate locations.

Extending through the base 6 from one edge 7 to the other edge 8 thereofis a first slide channel 13. This is defined to have its outer edge 14substantially parallel to the side edge 11 and to extend toward thecenter of the base, being somewhat narrower .as the center is approachedby reason of an intervening step 16.

Somewhat similarly, there is provided a second slide channel 17extending through the base 6 from the edge 7 to the edgeV 8 in adirection generally parallel to the side 9 and therefore parallel to thefirst channel 13. The second channel 17 is bounded by a side 21 parallelto the edge 9 and has a similar step 22. As the channel 17 narrows andapproaches the center of the base it merges with the comparable narrowportion of the first channel 13.

Also provided in the-base 6 is a third channel 24. This third channel isarranged with a boundary 26 parallel to the edge 3 and therefore atright angles to the sides 9 and 11. The third channel extendstransversely of the base from the edge 9 to the edge 11 thereof. Thisthird channel is formed in the laminations of the base in a positionabove the two channels 13 and 17 so that the third channel is entirelyseparate therefrom. The third channel overlies or spans the rst andsecond'channels. The third channel 24 is similarly provided with ashoulder 27 or step and a narrowed portion 28 comparable to the narrowedportions near the center of the first and second channels.

Designed to enter into and slide within the first channel 13 is a firstslide 31, particularly illustrated in FIGURE l. This is -generally arectangular sheet of material; for example, fiberboard, having parallelends and parallel side edges. The first slide 31 is provided along oneedge with a thickened rib 32 adapted to fit Well within the enlargedportion of the first channel 13 and is provided with a center plate 33adapted to extend into the narrow central portion and the merging partsof the first and second channels. The rib 32 of the first slidethroughout its length is provided with a series of transverse notehm 36.These are preferably approximately crescent shaped indentations into thematerial of the rib. Conveniently, these notches 36 are augmented onboth sides with linear markings 37. All of these are evenly spaced andcontinue largely throughout the length of the first slide. The slide 31also has a column of indicia 38 representing minutes from "0 to 9.

Additionally, the plate 33 of the first slide is provided with aplurality of elongated rectangular perforations such as 41, 42, 43 and44. The perforations enumerated are only some of a larger number ofsimilar perforations `appropriately arranged on the slide.

Disposed beneath the perforations 41, 42, 43 and 44 are appropriatelyspaced columns of indicia 48 and 49 appearing on the plate portion 51 ofa subposed second slide 52. This slide, like the iirst slide, is alsorectangular in plan and conveniently is made of a number of thicknessesof fiberboard. The plate portion 51 underlies in part the plate portion33 so that the thickness of the plate portions together is substantiallyequivalent to that of the merging central portions of the first andsecond channels. The second slide 52 has an upstanding edge rib S3substantially received in the enlarged portion of the second channel 17so as to be freely slidable therein in an endwise direction.

The rib 52 throughout substantially its entire length is provided with anumber of notches 54 or indentations also of substantially cresent shapelike the notches 36 and is similarly provided with adjacent delineations56. The relative arrangement of the first slide 31 and the second slide52 is such that the apertures 41, 42, 43 and 44 (and the additional,comparable apertures) are effective to disclose or uncover only selectedportions of certain columns of the indicia or numerals 48 and 49 invarious relatively shifted positions of the first and second slides.

To render the first and second slides readily useable and to `displayappropriate indicia, the base =6 in its central portion is formed todefine a cutout or rectangular window 61. This window extends part waythrough the base and leaves not only portions of the first slide 31exposed but also portions of the second slide 52 exposed. Furthermore,there are Within thewindow 61 subsidiary windows 62 and 63l overlyingthe subjacent central, plate portions of the first and second slides andof a width separately to disclose numerals in the column 48 andnurnerals in the column 49 insofar as such numerals are uncovered by theapertures 41, 42, 43 and 44 and the like. The window 63 also disclosesthe numerals in the column 38. The base 6 lwithin the window 61 andsurrounding the window 62 has a display area 64 on which appear numerals`66 representing tens of minutes and ranging from to 50, the mark for 60being unnumbered. The space 64 adjacent the irst slide 31 also carriesnumerals `67 representing minutes ranging from 0 to 9, the marker for110 being unnumbered. The window 62 carries the indicium 68 readinghours while the window 63 in the area `64 carries the indicium 69reading minutes.

In addition to the first and second slides there is provided a thirdslide 71 designed to traverse the third channel 24 freely in atransverse direction. The third slide has a thickened ribi 72 and a thinplate 73. These parts are substantially the same in cross-section as thecrosssection of the third transverse channel. On the thickened rib, thethird slide 71 carries a series of notches 74- comparable to theno-tches 36 and 54 while the plate 73 carries a series of indicia 77representing hours and ranging from 0 at the right-hand end to 24 at thelefthand end. The base 6 in addition to the 'window' 6i is alsoprovi-ded with a window 78 through which can be discerned the indicia 77on the subjacent third slide. Near the window 78 is an indicium 79reading hours Also adjacent the window 78 and disposed lin alignmenttherewith on the base 6i and in alignment also with the side marks 81 onthe third slide beside the notches 74- therein is a series of indicia 82at its center bearing the designation N representing noon in alignmentwith the window 78 and ranging toward the right with consecutivenumerals up to the final designation M indicating midnight and beginningat the left-hand end with a duplicate of the indicium M for midnight andranging with the numerals in order up to N representing noon.

The relative orientation yor positioning of the exposed portion of thethird slide 71 especially with respect to the exposed portion of theiirst slide 3-1 is such that while these slides are in different planesand each can be moved independently of the other, they are neverthelesssimultaneously available. A user can readily put his thumb 83 in aposition to engage the notches 74 with his thumbnail whilesimultaneously placing his index iinger 84 in a position so that hisngernail Ican engage the notches 36 of the first slide 31. The usersother hand can similarly be employed to actuate the second slide 52 andthe third slide 71 simultaneously.

In the use of this device, it is initially set at a zero reading in allthe windows by having the ends of the various slides flush with the endsand sides of the base 6. If then, for example, a work card shows that ajob started at 8:15 a.m., the user places the right hand thumb 83 withthe thumbnail in the notch 74 opposite the indicium 8 in the series 82,places the nail of a left hand iinger in the notch of the series 54-representing the tens of minutes; that is, i and puts the nail of hisright hand index finger 84 in the notch 36 opposite the numeral 5 in theindicium series 67. Suppose that the time card shows the job to havebeen terminated at 4:38 p.m. Under these circumstances the thumb 83 ismoved, carrying the third slide 7l with it to the right until such timeas the line 81 opposite the occupied notch registers with the lineadjacent the numeral 4 after noon in the series of indicia 82. Thesecond slide 52. is then moved so that the occupied notch originallyopposite lil in the series 66 is moved until it is opposite the numeral30 in that series. Further, the tirst slide 31 is moved until theoccupied one of the notches 36 is opposite the numeral 8 in the series67. All of these movements are such as to render a display of theelapsed time. Thus, the window 62 shows the numeral 0, the window 78shows the numeral 8 whereas the numeral 2 appears toward left in thewindow 63 and the numeral 3 appears to the right in the window 63indicating a reading of 8 hours 23 minutes.

In the event the starting and quitting times are such that there is anelapsed time of less than an hour even though the clock hour changes,the reading in the window 62 is subtracted from the reading in thewindow 73 since some of the numerals on the slide S2 in the indiciaseries 48 are in red to indicate subtraction whereas all of theremaining numerals are in black to indicate addition.

All other problems of elapsed time are accomplished in accordance withthe example explained, the user manipulating the three slides asdescribed. His work is greatly facilitated by the ability to manipulateboth the first and third slides or the second and third slidessimultaneously by the simultaneous operation of his thumb and indexfinger on the appropriately spaced movable parts. At the conclusion ofthe accumulation of any amount of clasped time within the capacity ofthe device, the various slides are all moved so that they are againflush with the boundaries of the base and so that the showing in thevarious windows is again zero, the device being then available for asubsequent problem.

By appropriately staggering the vario-us apertures 41, 42, 43 and 44 andby appropriately afiixing the indicia in the series 48 as well as in theseries 49, the various apertures, as the slides are moved, in eiiectshift from one column of indicia to another at an appropriate point soas to display a tens transfer. Thus, the device is correct and gives aproper indication of the true elapsed time no matter at what hour andminute the time period begins or at what hour and minute the time periodends. The only mental operation ever required from the user is apossible subtraction of the hourly figure in red appearing in thewindow' 62 from the hourly figure appearing in the window 7S, or apossible addition of hourly iigures in black appearing in the window 62to the hourly figure appearing in the window 78.

What is claimed is:

1. An elapsed time calculating device comprising a base having sides andends, means forming a first slide channel in said base parallel to saidsides, means forming a second slide channel in said base parallel tosaid sides and merging with said first channel, means forming a thirdchannel in said base parallel to said ends and overlying said firstchannel and said second channel, slides in said respective channelshaving numerals thereon, said slides being formed with operating notchestherein, and the slide in said third channel overlapping the slides insaid first and second channels, and means forming windows in said baseexposing selected areas of said slide numerals and selected groups ofsaid notches in locations -for simultaneous manipulation of the slide insaid third channel and one of the slides in said first and secondchannels by the thumb and iinger of one hand of the user.

2. An elapsed time calculating device comprising a planar, rectangularbase having sides and ends, means forming a iirst 'channel in said baseparallel to said sides and extending from end to end, means forming asecond channel in said base parallel to said sides and extending fromend to end and Imerging with said iirst channel, means forming a thirdchannel in said base parallel to said ends and extending from side toside and overlying said hrst channel and said second channel, slides insaid channels having numerals thereon, means forming windows in saidbase for exposing selected portions of said slides andthe numeralsthereon, and means forming notches on said slides accessible throughsaid windows to the thumb and finger of a user said notches on saidslides in said first and second channels being parallel to said ends andsaid notches on said slide in said third channel being parallel to saidsides.

References Cited in the file of this patent UNITED STATES PATENTS689,680 Locke Dec. 24, l1 1,114,560 Wild Oct. 20, 1914 1,422,944Edmondson July 18, 1922 2,605,04s Jordan July 29, 1952 2,659,632Brickner Nov. 17, 1953 FOREGN PATENTS 568,876 France Jan. 2, 1924

